1. Field of the Invention
Embodiments of the invention relate generally to medical laser systems and, more particularly, to a method of initiating an optical fiber of a tip assembly. The initiation employs the use of a metal colored enamel or initiating material that results in the finished, initiated optical fiber being impregnated with metal particles or flakes. The adhesion or bond of the metal particles or flakes to the optical fiber is superior to that of carbon based materials, non-organic, synthetic, or non-metal based pigments impregnated into optical fibers in accordance with existing initiation techniques.
2. Background
Lasers find application in a variety of medical and dental treatment procedures, where some of the most common operations involve cutting, ablation, disinfection, or other treatment of tissue. Depending on the particular wavelength, output power, and pulse width of the laser emission, as well as the absorptivity of the target tissue, varying biological materials from soft tissue such as muscles and skin, to hard tissue such as teeth and bones, can be cut and ablated. Laser systems with output power levels up to the tens of watts can be used for these applications, although lower powered laser systems with output power levels in the 10 milliwatt range can be used in microbicidal applications, tissue biostimulation applications, low-level light therapy, and other non-tissue-destructive applications.
A conventional laser system generally includes three primary components: a laser medium that generates the laser light, a power supply that delivers energy to the laser medium in the form needed to excite the same to emit coherent light, and an optical cavity or resonator that concentrates the light to stimulate the emission of laser radiation. Laser emissions can range from ultraviolet wavelengths, visible light wavelengths, to infrared wavelengths, depending on the type of laser medium utilized, and whether the medium comprises one or more gases, chemicals, dyes, metal vapors, and whether the laser is solid state, or semiconductor, etc.
Conventional laser systems suitable for surgical applications are generally comprised of the aforementioned laser energy source and a separate hand-piece coupled thereto that can be manually operated by the practitioner. In a basic implementation, the hand-piece includes a tip assembly comprising an optical fiber that is in optical communication with a waveguide and hence the laser energy source. The output end or surface of the optical fiber directs the emitted laser energy on to a target tissue site, and varying shape configurations can yield different output profiles, including simple circular patterns. The laser emission can be directed at any angle that maximizes operator flexibility and comfort in accessing the target tissue site. The optical pathway can be offset from a connecting cable/handpiece axis using different reflector arrangements.
In many conventional laser devices suitable for medical applications, there is a requirement that the practitioner, clinician or other user of the device “initiate” any new optical fiber integrated into the tip assembly. The general objective of the initiation process is to facilitate the impregnation of certain organic or non-organic materials into the distal portion of the optical fiber that results in at least a portion of the laser energy applied through the optical fiber being partially absorbed and converted into heat.
In one currently known, often used initiation process, an initiation block is provided, such block typically being fabricated from cork, a carbon based organic material. The initiation process is facilitated by initially touching the distal end of the optical fiber to the exposed top surface of the block. Thereafter, the laser is fired, allowing the optical fiber to sink into or burn its way into the block. Then, the optical fiber is pulled from within the block. The laser continues to be fired until the optical fiber has been completely removed from the block. Upon the removal of the optical fiber from block, the laser is fired once into the air, which typically results in the appearance of a glowing distal end portion of the optical fiber. A glowing distal end portion indicates that the initiation has been successful, and that the optical fiber, and hence the tip assembly, is ready for use. Other currently known initiation processes follow a similar protocol, but employ the use of carbon-based organic materials other than for cork (e.g., organic pigments), or non-organic (synthetic), non-metal based pigments.
This known initiation process is intended to facilitate the impregnation of any one of the aforementioned initiating materials into a distal portion of the optical fiber to facilitate the functional objectives described above. However, the primary deficiency arising from the use of these particular initiating materials lies in their inability to create good adhesion or a good chemical bond to the glass during the melting thereof which occurs during the initiation process.